• 조명전기설비학회논문지
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• 제23권10호
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• pp.128-133
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• 2009

본 논문에서는 전류보조전극 및 전위보조전극의 접지저항 측정위치에 따른 접지저항 측정결과를 비교 분석하였다. 국내의 경우 접지전극의 대각선 길이의 6.5배 이상에서 접지저항을 측정하고 있으나 도심지역에서는 이와 같은 방법은 한계를 나타내고 있다. 이를 해결하기 위해 본 논문에서는 접지저항 측정시 접지전극, 전류보조전극과 전위 보조전극간의 거리, 각도를 변경하여 접지저항을 측정하였다. 측정결과 접지전극과 전류보조전극간의 거리를 50[m] 이상, 전위보조전극을 30[m] 이상 이격을 하고 전류보조전극과 전위보조전극을 45도 이상 각도를 유지할 경우 안정적인 접지저항이 측정되었다.

• Journal of Electrochemical Science and Technology
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• 제9권3호
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• pp.220-228
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• 2018

This study introduced a carbon-free electrode for $Li-O_2$ cells with the aim of suppressing the side reactions activated by carbon material. Micro-particles of poly(3,4-ethylenedioxythiophene) (PEDOT), a conducting polymer, were used as the base material for the air electrode of $Li-O_2$cells. The PEDOT micro-particles were treated with $H_2SO_4$ to improve their electronic conductivity, and LiBr and CsBr were used as the redox mediators to facilitate the dissociation of there action products in the electrode and reduce the over-potential of the $Li-O_2$ cells. The capacity of the electrode employing PEDOT micro-particles was significantly enhanced via $H_2SO_4$ treatment, which is attributed to the increased electronic conductivity. The considerable capacity enhancement and relatively low over-potential of the electrode employing $H_2SO_4$-treated PEDOT micro-particles indicate that the treated PEDOT micro-particles can act as reaction sites and provide storage space for the reaction products. The cyclic performance of the electrode employing $H_2SO_4$-treated PEDOT micro-particles was superior to that of a carbon electrode. The results of the Fourier-transform infrared spectroscopic analysis showed that the accumulation of residual reaction products during cycling was significantly reduced by introducing the carbon-free electrode based on $H_2SO_4$-treated PEDOT micro-particles, compared with that of the carbon electrode. The cycle life was improved owing to the effect of the redox mediators. The refore, the use of the carbon -free electrode combined with redox mediators could realize excellent cyclic performance and low over-potential simultaneously.

• 조명전기설비학회논문지
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• 제15권2호
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• pp.97-104
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• 2001

본 논문에서는 전위강하법에 의한 접지저항 측정시 전위보조전극 위치의 영향에 대하여 기술하였다. 전위강하법에서 접지저항은 이론적으로 전위보조전극을 피측정 접지전극과 전류보조전극이 이루는 일직선상에 위치시킬때 61.8[%]법칙을 적용하여 측정한다. 하지만 측정현장의 사정상 전위보조전극의 위치를 피측정 접지전극과 전류 보조전극이 이루는 일직선과 어느 정도의 각도를 가지도록 시설하여 접지저항을 측정하게 될 경우에 측정오차가 발생하게 되고 보정이 필요하다. 본 연구에서의 측정대상 전극은 길이 2.4 [m]의 봉형 접지전극으로 하였으며, 피측정 접지전극, 전위보조전극, 전류보조전극이 일직선상에 놓이지 않은 상태에서 접지저항을 측정하면 측정값은 항상 (-)의 오차를 나타내었고, 이들 전극이 이루는 각도가 증가함에 따라 측정 오차도 증가하였다.

• Bulletin of the Korean Chemical Society
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• 제30권12호
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• pp.2943-2948
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• 2009

Copper-dimethylglyoxime complex (CuDMG) modified Copper electrode (Cu/CuDMG) showed a catalytic activity towards cyclohexanol oxidation in NaOH solution. The modified electrode prepared by the dimethylglyoxime anodic deposition on Cu electrode in the solution contained 0.20 M $NH_4Cl\;+\;NH_4OH\;(pH\;9.50)\;and\;1\;{\times}\;10^{-4}$ M dimethylglyoxime. The modified electrode conditioned by potential recycling in a potential range of -900${\sim}$900 mV vs. Ag/AgCl by cyclic voltammetry in alkaline medium (1 M NaOH). The results show that the CuDMG film on the electrode behaves as an efficient catalyst for the electro-oxidation of cyclohexanol in alkaline medium via Cu (III) species formed on the electrode.

• Corrosion Science and Technology
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• 제7권3호
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• pp.179-181
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• 2008

With nano-$SiO_2$ and sulphate acid, a kind of colloid electrolyte is synthesized by sol-gel method. It is placed outside the reference electrode as a layer of gel electrolyte so as to decrease the leaching of $Cu^{2+}$ and increase the life of the reference electrode. The performance of the gel electrode in simulating soil solution is measured as follows: the potential of the electrodes ranging from 60 mV to 80 mV (vs. SCE) with potential variation no more than $\pm10mV$, enough resistance to polarization. The $Cu^{2+}$ effusion rate of the reference electrode without gel electrolyte is 3 times that with colloid electrolyte, which means that gel electrolyte can extend the life of the reference electrode significantly.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 학술대회 논문집 전문대학교육위원
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• pp.108-112
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• 2000

The electric charge generated by flowing insulation liquid can create hazardous spark in transfer line and receiving tank etc. These electrification has generally been measured by current measurement with a ammeter connected to the receiving tank. This paper reports on the experimental result obtained by this method. As a experimental results: The injected charge value for unit volume increased in the following condition, the edge of the needle electrode was sharp, the number of needle electrode was fewer, the edge of the needle electrode was located close to the inside wall. When the charge density in the charge reducer is constant, electrode current and electrode potential by the charge injection from outside increase with increasing of oil velocity and streaming current. The electrode potential in charge reducer is made maximum value at edge point of reducer inside and minimum value at center line of charge reducer.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제54권7호
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• pp.319-325
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• 2005

In order to analyze ground potential rise of grounding system installed in buildings, the hemispherical grounding simulation system has been designed and fabricated as substantial and economical measures. Ground potential rise(GPR) has been measured and analyzed for shapes of grounding electrode using the system in real time. The system is apparatus to have a free reduced scale for conductor size and laying depth of a full scale grounding system and is constructed so that a shape of equipotential surface is nearly identified a free reduced scale with a real scale when a current flows through grounding electrode. The system was composed of a hemispherical water tank, AC Power supply, a movable potentiometer, and test grounding electrodes. The test grounding electrodes were fabricated through reducing grounding electrode installed in real buildings such as rod type, mesh grid type. When a mesh grid type was associated with a rod type, GPR was the lowest value. The proposed results would be applicable to evaluate GPR in the grounding systems. and the analytical data can be used 0 stabilize the electrical installations and prevent the electrical disasters.

• 대한화학회지
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• 제15권6호
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• pp.347-352
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• 1971

The variations of the positive and negative electrode potentials, and of internal pressure were measured during the charge of the sealed type Ni-Cd cell. Both polarization characteristics of a paste type Cd-electrode as a gas diffusion electrode in 30% KOH solution and the effects of active carbon electrode as an oxygen consuming auxiliary electrode of the Ni-Cd cell on the charging characteristics of the cell were studied. Peak voltage at the end of charge of the cell is ascribed to the peak at the negative electrode potential, which is due to the concentration polarization by the lack of $Cd^{++}$ ion and oxygen concentration. And the recovery of the negative electrode potential is resulted from depolarization by the increasing diffusion limiting current density with the increasing oxygen pressure. The active carbon electrode was effective as an oxygen consuming auxiliary electrode. The internal pressure of the cell could be maintained below 200mmHg even at one hour rate charge and overcharge by the use of active carbon electrode as an auxiliary electrode.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 E
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• pp.2284-2286
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• 1999

This paper describes the development of potential detection system in 22.9kV gas insulated switchgear. This system composed with main system and LPS can detect the source voltage by capacitive potential division which is accomplished by inserting signal electrode between main electrode and earthed metal enclosure of the switchgear. The appropriate position of signal electrode is achieved by numerical analysis using finite element method. The developed potential detection system is verified by several tests such as voltage test, swc test and others and by applicaion at site. From the results, it is concluded that potential detection system is very reliable and available to operate the switchgear safely.

• 분석과학
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• 제20권1호
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• pp.49-54
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• 2007

For the practical use as a biosensor, a rubber electrode bound by polybutadiene was newly devised for the determination of hydrogen peroxide. Then its electrochemical behaviors were investigated. The signal could be obtained at low electrode potential between 0.0 ~ -0.5 V (vs. Ag/AgCl) with a detection limit of $1.4{\times}10^{-4}M$ and its potential dependence was linear in the experimental range. Especially its Lineweaver-Burk plot showed a very good linearity giving the evidence of a good enzyme immobilization on the surface of the electrode. And mechanical stability of the electrode resulted from using rubber binder presented a new possibility for the practical use of biosensor.